An output voltage is compared to a reference voltage, comparison signals are generated, and control signals and mode signals are generated in response thereto. The output voltage is generated in response to the control signals. A speed of the comparing is increased in response to the mode signals indicating that the output voltage is being increased. The speed is reduced in response to the mode signals indicating that the output voltage is being reduced. For increasing the speed, a path is enabled to conduct current. While the path is enabled, at least one switched voltage is connected to vary an amount of the current conducted through the path. The switched voltage is at least one of the reference voltage and the output voltage. For reducing the speed, the path is disabled against conducting current. While the path is disabled, the switched voltage is disconnected from varying the amount.